TONIGHT'S MUST-SEE

"Saturday Night Live," 10:30 p.m., NBC. The world has become newly interested in the big, broad and unwieldy "Saturday Night Live." Fictional versions of the show provide the backdrop for two new NBC series - Aaron Sorkin's great "Studio 60 on the Sunset Strip" and Tina Fey's fairly good "30 Rock," which begins Oct. 11. Alongside those fictional versions, the real "SNL" starts its 31st year. That's right, 31. The opener is hosted by Dane Cook, who's been busy lately. On HBO, he's had a comedy special and a reality show. In theaters, he has one new movie, "Employee of the Month," and two more on the way. The Killers will be tonight's musical guests. The show had grown to 16 sketch players, but the cast will trim down now. Fey and Rachel Dratch left for "30 Rock," and Horatio Sanz, Chris Parnell and Finesse Mitchell are also gone. Seth Meyers will take Fey's spot on the "Weekend Update" desk alongside Amy Poehler. Meyers continues to be one of the three head writers. Andrew Steele also continues in that job, and Paula Pell takes Fey's head-writer spot.

OF NOTE

"Unwrapping Macy's," 4 p.m., WE; repeats at 4:30, 9 & 9:30 p.m. This eight-week documentary looks at the inner workings of the giant Macy's department store chain. In this opener, a male fashion catalog is planned and a staffer savors her job of auditioning young models with rippling torsos. Also shown is the effort of a new shoe company started by twin designers Shane and Shawn Ward, handsome guys who grew up in a modest-income Detroit family. Both are instantly likable.

"Drake & Josh Go Hollywood," 5 p.m., Nickelodeon. In this movie-length version of the "Drake & Josh" teen series, the guys accidentally send their little sister on the wrong plane. Then they try to retrieve her.

"The Class," 7 and 7:30 p.m., CBS. Here's a second chance to catch the start of the best new comedy in years. The first rerun has Ethan (Jason Ritter) surprising his fiancee by gathering their third-grade classmates. The night soon crumbles for him. Others make key connections, leading to some great moments in the second rerun.

"CSI: Crime Scene Investigation," 8 p.m., CBS. When the body of a teen girl is found, officials are sure they have the killer. Then someone else confesses from the witness stand.